Rational modification of substrate binding site by structure-based engineering of a cellobiose 2-epimerase in Caldicellulosiruptor saccharolyticus.

These results showed that the Y114E mutation increased isomerization of lactose, while decreasing the epimerization of lactose. Thus, a subtle modification of the active site pocket could extend its native activity from epimerization to isomerization without significantly impairing substrate binding. While additional studies are required to scale this to an industrial process, we demonstrated the potential of engineering this enzyme based on structural analysis.